If you're going to give them a compliment, do it in front of their lady, so there's no flirtation implied. Unless she's an insecure bitch, then don't bother, it's not worth the hassle for him or you.
Having a coffee or a drink alone with a dude is a bad idea, unless you are the rarest of friends (in my 50 years I've had exactly one female friend who I can hang out with alone without an undercurrent of tension). Guys are animals deep down, and spending time alone with them is giving them a signal, whether you mean it or not.